Recently, information services for delivering electronic information have been increasingly used in various fields. For example, using information about locations, services may be provided to a person at a particular location.
For example, as a technique to determine whether or not a user is at a location where a service is provided, a beacon sending device is installed at the location where the service is provided. A receiving device (a communication device) carried by the user continuously searches for a beacon. If a beacon from the sending device is received, the receiving device determines that the sending device has arrived at the location. Additionally, if the receiving device carried by the user has become unable to receive a beacon from the sending device, the receiving device determines that the sending device has left that location.
Specifically, with iBeacon (registered trademark), a terminal (a receiving device, a communication device) of the user continuously searches for a beacon. When the terminal of the user receives a beacon from a beacon sending device installed at a location where a service is provided, the service is provided, and, when the terminal has become unable to receive a beacon, the service provision is stopped.
The beacon sending device intermittently sends signals. For this reason, the receiving device, upon receiving beacons from a sending device installed at a location where a service is provided, may control radio frequency (RF) receiving unit if the sending intervals of the beacons are detected.
That is, the receiving device causes the RF receiving unit, which receives a radio signal, to be in the operating state (ON) at a timing at which a beacon is sent, and to be in the stopped state (OFF) after completion of signal reception. This enables the power consumption to be reduced.
Various proposals have been offered as reception control techniques for receiving beacons intermittently sent from a beacon sending device. As related art techniques, for example, Japanese Laid-open Patent Publication No. 2005-184606, Japanese Laid-open Patent Publication No. 63-301627, and Japanese Laid-open Patent Publication No. 4-120920 are disclosed.
As described above, for example, as a receiving device, a device in which the RF receiving unit is caused to be ON at a timing at which a beacon is sent and to be OFF after completion of signal reception, thereby reducing the power consumption, has been devised.
However, in some beacon sending devices, information on sending intervals are not contained in the signals sent, or the sending intervals vary. To receive every one of the signals received from such a beacon sending device, the RF receiving unit has to remain ON. As a result, a problem arises in that power consumption of the receiving device increases.
To quickly determine that the receiving device has left from a location for service provision, it is desirable that every one of the signals intermittently sent by the beacon sending device be received. However, the receiving device does not necessarily cause the RF receiving unit to be ON when the beacon sending device is sending signals.
Therefore, a problem arises in that signals sent when the RF receiving unit is OFF are not received, lengthening the time taken to detect that the receiving device has left from a location for service provision. Furthermore, another problem arises in that the RF receiving unit is ON even when the sending device is not sending a signal, resulting in wasteful power consumption.